From 99c350f5550237cf14e6d90149e87837b995c11b Mon Sep 17 00:00:00 2001
From: Naushir Patuck <naush@raspberrypi.com>
Date: Fri, 10 Mar 2023 17:43:57 +0000
Subject: [PATCH] media: imx219: Advertise embedded data node on media
 pad 1

This commit updates the imx219 driver to adverise support for embedded
data streams.  This can then be used by the bcm2835-unicam driver, which
has recently been updated to expose the embedded data stream to
userland.

The imx219 sensor subdevice overloads the media pad to differentiate
between image stream (pad 0) and embedded data stream (pad 1) when
performing the v4l2_subdev_pad_ops functions.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/media/i2c/imx219.c | 243 ++++++++++++++++++++++++-------------
 1 file changed, 161 insertions(+), 82 deletions(-)

--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -126,6 +126,16 @@
 #define IMX219_PIXEL_ARRAY_WIDTH	3280U
 #define IMX219_PIXEL_ARRAY_HEIGHT	2464U
 
+/* Embedded metadata stream structure */
+#define IMX219_EMBEDDED_LINE_WIDTH 16384
+#define IMX219_NUM_EMBEDDED_LINES 1
+
+enum pad_types {
+	IMAGE_PAD,
+	METADATA_PAD,
+	NUM_PADS
+};
+
 struct imx219_reg {
 	u16 address;
 	u8 val;
@@ -448,7 +458,7 @@ static const struct imx219_mode supporte
 
 struct imx219 {
 	struct v4l2_subdev sd;
-	struct media_pad pad;
+	struct media_pad pad[NUM_PADS];
 
 	struct v4l2_mbus_framefmt fmt;
 
@@ -598,18 +608,26 @@ static void imx219_set_default_format(st
 static int imx219_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 {
 	struct imx219 *imx219 = to_imx219(sd);
-	struct v4l2_mbus_framefmt *try_fmt =
-		v4l2_subdev_get_try_format(sd, fh->state, 0);
+	struct v4l2_mbus_framefmt *try_fmt_img =
+		v4l2_subdev_get_try_format(sd, fh->state, IMAGE_PAD);
+	struct v4l2_mbus_framefmt *try_fmt_meta =
+		v4l2_subdev_get_try_format(sd, fh->state, METADATA_PAD);
 	struct v4l2_rect *try_crop;
 
 	mutex_lock(&imx219->mutex);
 
 	/* Initialize try_fmt */
-	try_fmt->width = supported_modes[0].width;
-	try_fmt->height = supported_modes[0].height;
-	try_fmt->code = imx219_get_format_code(imx219,
-					       MEDIA_BUS_FMT_SRGGB10_1X10);
-	try_fmt->field = V4L2_FIELD_NONE;
+	try_fmt_img->width = supported_modes[0].width;
+	try_fmt_img->height = supported_modes[0].height;
+	try_fmt_img->code = imx219_get_format_code(imx219,
+						   MEDIA_BUS_FMT_SRGGB10_1X10);
+	try_fmt_img->field = V4L2_FIELD_NONE;
+
+	/* Initialize try_fmt for the embedded metadata pad */
+	try_fmt_meta->width = IMX219_EMBEDDED_LINE_WIDTH;
+	try_fmt_meta->height = IMX219_NUM_EMBEDDED_LINES;
+	try_fmt_meta->code = MEDIA_BUS_FMT_SENSOR_DATA;
+	try_fmt_meta->field = V4L2_FIELD_NONE;
 
 	/* Initialize try_crop rectangle. */
 	try_crop = v4l2_subdev_get_try_crop(sd, fh->state, 0);
@@ -723,12 +741,22 @@ static int imx219_enum_mbus_code(struct
 {
 	struct imx219 *imx219 = to_imx219(sd);
 
-	if (code->index >= (ARRAY_SIZE(codes) / 4))
+	if (code->pad >= NUM_PADS)
 		return -EINVAL;
 
-	mutex_lock(&imx219->mutex);
-	code->code = imx219_get_format_code(imx219, codes[code->index * 4]);
-	mutex_unlock(&imx219->mutex);
+	if (code->pad == IMAGE_PAD) {
+		if (code->index >= (ARRAY_SIZE(codes) / 4))
+			return -EINVAL;
+
+		mutex_lock(&imx219->mutex);
+		code->code = imx219_get_format_code(imx219, codes[code->index * 4]);
+		mutex_unlock(&imx219->mutex);
+	} else {
+		if (code->index > 0)
+			return -EINVAL;
+
+		code->code = MEDIA_BUS_FMT_SENSOR_DATA;
+	}
 
 	return 0;
 }
@@ -740,19 +768,32 @@ static int imx219_enum_frame_size(struct
 	struct imx219 *imx219 = to_imx219(sd);
 	u32 code;
 
-	if (fse->index >= ARRAY_SIZE(supported_modes))
+	if (fse->pad >= NUM_PADS)
 		return -EINVAL;
 
-	mutex_lock(&imx219->mutex);
-	code = imx219_get_format_code(imx219, fse->code);
-	mutex_unlock(&imx219->mutex);
-	if (fse->code != code)
-		return -EINVAL;
+	if (fse->pad == IMAGE_PAD) {
+		if (fse->index >= ARRAY_SIZE(supported_modes))
+			return -EINVAL;
+
+		mutex_lock(&imx219->mutex);
+		code = imx219_get_format_code(imx219, fse->code);
+		mutex_unlock(&imx219->mutex);
+		if (fse->code != code)
+			return -EINVAL;
+
+		fse->min_width = supported_modes[fse->index].width;
+		fse->max_width = fse->min_width;
+		fse->min_height = supported_modes[fse->index].height;
+		fse->max_height = fse->min_height;
+	} else {
+		if (fse->code != MEDIA_BUS_FMT_SENSOR_DATA || fse->index > 0)
+			return -EINVAL;
 
-	fse->min_width = supported_modes[fse->index].width;
-	fse->max_width = fse->min_width;
-	fse->min_height = supported_modes[fse->index].height;
-	fse->max_height = fse->min_height;
+		fse->min_width = IMX219_EMBEDDED_LINE_WIDTH;
+		fse->max_width = fse->min_width;
+		fse->min_height = IMX219_NUM_EMBEDDED_LINES;
+		fse->max_height = fse->min_height;
+	}
 
 	return 0;
 }
@@ -767,9 +808,9 @@ static void imx219_reset_colorspace(stru
 	fmt->xfer_func = V4L2_MAP_XFER_FUNC_DEFAULT(fmt->colorspace);
 }
 
-static void imx219_update_pad_format(struct imx219 *imx219,
-				     const struct imx219_mode *mode,
-				     struct v4l2_subdev_format *fmt)
+static void imx219_update_image_pad_format(struct imx219 *imx219,
+					   const struct imx219_mode *mode,
+					   struct v4l2_subdev_format *fmt)
 {
 	fmt->format.width = mode->width;
 	fmt->format.height = mode->height;
@@ -777,21 +818,39 @@ static void imx219_update_pad_format(str
 	imx219_reset_colorspace(&fmt->format);
 }
 
+static void imx219_update_metadata_pad_format(struct v4l2_subdev_format *fmt)
+{
+	fmt->format.width = IMX219_EMBEDDED_LINE_WIDTH;
+	fmt->format.height = IMX219_NUM_EMBEDDED_LINES;
+	fmt->format.code = MEDIA_BUS_FMT_SENSOR_DATA;
+	fmt->format.field = V4L2_FIELD_NONE;
+}
+
 static int __imx219_get_pad_format(struct imx219 *imx219,
 				   struct v4l2_subdev_state *sd_state,
 				   struct v4l2_subdev_format *fmt)
 {
+	if (fmt->pad >= NUM_PADS)
+		return -EINVAL;
+
 	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
 		struct v4l2_mbus_framefmt *try_fmt =
 			v4l2_subdev_get_try_format(&imx219->sd, sd_state,
 						   fmt->pad);
 		/* update the code which could change due to vflip or hflip: */
-		try_fmt->code = imx219_get_format_code(imx219, try_fmt->code);
+		try_fmt->code = fmt->pad == IMAGE_PAD ?
+				imx219_get_format_code(imx219, try_fmt->code) :
+				MEDIA_BUS_FMT_SENSOR_DATA;
 		fmt->format = *try_fmt;
 	} else {
-		imx219_update_pad_format(imx219, imx219->mode, fmt);
-		fmt->format.code = imx219_get_format_code(imx219,
-							  imx219->fmt.code);
+		if (fmt->pad == IMAGE_PAD) {
+			imx219_update_image_pad_format(imx219, imx219->mode,
+						       fmt);
+			fmt->format.code = imx219_get_format_code(imx219,
+								  imx219->fmt.code);
+		} else {
+			imx219_update_metadata_pad_format(fmt);
+		}
 	}
 
 	return 0;
@@ -821,59 +880,78 @@ static int imx219_set_pad_format(struct
 	int exposure_max, exposure_def, hblank;
 	unsigned int i;
 
-	mutex_lock(&imx219->mutex);
-
-	for (i = 0; i < ARRAY_SIZE(codes); i++)
-		if (codes[i] == fmt->format.code)
-			break;
-	if (i >= ARRAY_SIZE(codes))
-		i = 0;
+	if (fmt->pad >= NUM_PADS)
+		return -EINVAL;
 
-	/* Bayer order varies with flips */
-	fmt->format.code = imx219_get_format_code(imx219, codes[i]);
+	mutex_lock(&imx219->mutex);
 
-	mode = v4l2_find_nearest_size(supported_modes,
-				      ARRAY_SIZE(supported_modes),
-				      width, height,
-				      fmt->format.width, fmt->format.height);
-	imx219_update_pad_format(imx219, mode, fmt);
-	if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
-		framefmt = v4l2_subdev_get_try_format(sd, sd_state, fmt->pad);
-		*framefmt = fmt->format;
-	} else if (imx219->mode != mode ||
-		   imx219->fmt.code != fmt->format.code) {
-		u32 prev_hts = imx219->mode->width + imx219->hblank->val;
-
-		imx219->fmt = fmt->format;
-		imx219->mode = mode;
-		/* Update limits and set FPS to default */
-		__v4l2_ctrl_modify_range(imx219->vblank, IMX219_VBLANK_MIN,
-					 IMX219_VTS_MAX - mode->height, 1,
-					 mode->vts_def - mode->height);
-		__v4l2_ctrl_s_ctrl(imx219->vblank,
-				   mode->vts_def - mode->height);
-		/* Update max exposure while meeting expected vblanking */
-		exposure_max = mode->vts_def - 4;
-		exposure_def = (exposure_max < IMX219_EXPOSURE_DEFAULT) ?
-			exposure_max : IMX219_EXPOSURE_DEFAULT;
-		__v4l2_ctrl_modify_range(imx219->exposure,
-					 imx219->exposure->minimum,
-					 exposure_max, imx219->exposure->step,
-					 exposure_def);
-		/*
-		 * Retain PPL setting from previous mode so that the
-		 * line time does not change on a mode change.
-		 * Limits have to be recomputed as the controls define
-		 * the blanking only, so PPL values need to have the
-		 * mode width subtracted.
-		 */
-		hblank = prev_hts - mode->width;
-		__v4l2_ctrl_modify_range(imx219->hblank,
-					 IMX219_PPL_MIN - mode->width,
-					 IMX219_PPL_MAX - mode->width,
-					 1,
-					 IMX219_PPL_MIN - mode->width);
-		__v4l2_ctrl_s_ctrl(imx219->hblank, hblank);
+	if (fmt->pad == IMAGE_PAD) {
+		for (i = 0; i < ARRAY_SIZE(codes); i++)
+			if (codes[i] == fmt->format.code)
+				break;
+		if (i >= ARRAY_SIZE(codes))
+			i = 0;
+
+		/* Bayer order varies with flips */
+		fmt->format.code = imx219_get_format_code(imx219, codes[i]);
+
+		mode = v4l2_find_nearest_size(supported_modes,
+					      ARRAY_SIZE(supported_modes),
+					      width, height,
+					      fmt->format.width,
+					      fmt->format.height);
+		imx219_update_image_pad_format(imx219, mode, fmt);
+		if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+			framefmt = v4l2_subdev_get_try_format(sd, sd_state,
+							      fmt->pad);
+			*framefmt = fmt->format;
+		} else if (imx219->mode != mode ||
+			   imx219->fmt.code != fmt->format.code) {
+			u32 prev_hts = imx219->mode->width + imx219->hblank->val;
+
+			imx219->fmt = fmt->format;
+			imx219->mode = mode;
+			/* Update limits and set FPS to default */
+			__v4l2_ctrl_modify_range(imx219->vblank,
+						 IMX219_VBLANK_MIN,
+						 IMX219_VTS_MAX - mode->height,
+						 1,
+						 mode->vts_def - mode->height);
+			__v4l2_ctrl_s_ctrl(imx219->vblank,
+					   mode->vts_def - mode->height);
+			/* Update max exposure while meeting expected vblanking */
+			exposure_max = mode->vts_def - 4;
+			exposure_def = (exposure_max < IMX219_EXPOSURE_DEFAULT) ?
+				exposure_max : IMX219_EXPOSURE_DEFAULT;
+			__v4l2_ctrl_modify_range(imx219->exposure,
+						 imx219->exposure->minimum,
+						 exposure_max,
+						 imx219->exposure->step,
+						 exposure_def);
+			/*
+			 * Retain PPL setting from previous mode so that the
+			 * line time does not change on a mode change.
+			 * Limits have to be recomputed as the controls define
+			 * the blanking only, so PPL values need to have the
+			 * mode width subtracted.
+			 */
+			hblank = prev_hts - mode->width;
+			__v4l2_ctrl_modify_range(imx219->hblank,
+						 IMX219_PPL_MIN - mode->width,
+						 IMX219_PPL_MAX - mode->width,
+						 1,
+						 IMX219_PPL_MIN - mode->width);
+			__v4l2_ctrl_s_ctrl(imx219->hblank, hblank);
+		}
+	} else {
+		if (fmt->which == V4L2_SUBDEV_FORMAT_TRY) {
+			framefmt = v4l2_subdev_get_try_format(sd, sd_state,
+							      fmt->pad);
+			*framefmt = fmt->format;
+		} else {
+			/* Only one embedded data mode is supported */
+			imx219_update_metadata_pad_format(fmt);
+		}
 	}
 
 	mutex_unlock(&imx219->mutex);
@@ -1490,12 +1568,13 @@ static int imx219_probe(struct i2c_clien
 	imx219->sd.entity.function = MEDIA_ENT_F_CAM_SENSOR;
 
 	/* Initialize source pad */
-	imx219->pad.flags = MEDIA_PAD_FL_SOURCE;
+	imx219->pad[IMAGE_PAD].flags = MEDIA_PAD_FL_SOURCE;
+	imx219->pad[METADATA_PAD].flags = MEDIA_PAD_FL_SOURCE;
 
 	/* Initialize default format */
 	imx219_set_default_format(imx219);
 
-	ret = media_entity_pads_init(&imx219->sd.entity, 1, &imx219->pad);
+	ret = media_entity_pads_init(&imx219->sd.entity, NUM_PADS, imx219->pad);
 	if (ret) {
 		dev_err(dev, "failed to init entity pads: %d\n", ret);
 		goto error_handler_free;
